Decorative panel and method for producing a panel

ABSTRACT

The invention relates to a decorative panel, in particular a floor panel, wall panel or ceiling panel, the panel comprising at least one core layer comprising an upper core surface and a bottom core surface, wherein the core layer comprises a composite material comprising at least one mineral material and at least one polymer and at least one top layer comprising at least one ply of resin impregnated paper, wherein the core layer has a predetermined Vicat softening temperature and wherein the upper core surface of the core layer has a predetermined Shore D hardness such that a panel is obtained which has good waterproof- and scratch resistant properties.

The invention relates to a decorative panel, in particular a floorpanel, wall panel or ceiling panel. The invention also relates to amethod for producing a decorative panel.

Research is done in flooring in order to attempt to combine theadvantages of a thermoplastic core material (water resistance) and athermosetting resin impregnated cellulose top layer (scratchresistance). Difficulties arise when trying to sufficiently bond thedifferent layers without being sensitive to delamination or having touse a rather complex production process. A thermoplastic composite corecan generally not withstand the pressure and heat required to cure theuncured resins impregnating the top layer, nor the heat required toactivate the hardener present in the polymeric adhesive bonding the coreand top layer together. Thermoplastics such as polyvinyl chloride (PVC)core are known to soften and even melt completely at elevatedtemperatures, for example PVC which has a low Vicat softeningtemperature at about 65 degrees Celsius and a melting point around 150degrees Celsius. When attempting to produce according to the prior art,this deformation of the core leads to uneven thicknesses, fractures ofthe rigid top layers and the like. As a thermosetting resin impregnatingthe top layer, for example melamine resin, is known to only cure attemperatures higher than 150 degrees Celsius, increasing the viscosityand rigidity of the core at a higher temperature is required. Further,the adhesion of a thermosetting top layer on a thermoplastic corenecessitates the use of an adhesive layer comprising a thermosettingresin and a polymeric adhesive or epoxy which requires heat higher than150 degrees Celsius to activate.

It is an objective of the invention, to at least partially limit oreliminate the above indicated drawbacks of the known process forproducing a panel or at least to provide an alternative to the currentstate of the art.

The invention thereto relates to a decorative panel, in particular afloor panel, wall panel or ceiling panel, the panel comprising:

-   -   at least one core layer comprising an upper core surface and a        bottom core surface and preferably two pairs of opposing side        edges, wherein the core layer comprises a composite material        comprising at least one mineral material and/or at least one        polymer; and    -   at least one top layer comprising at least one ply of resin        impregnated paper;        wherein at least one ply of paper is impregnated with a resin        composition comprising at least one thermosetting resin and/or        at least one polymeric adhesive;        wherein the core layer has a Vicat softening temperature of at        least 80 degrees Celsius, preferably at least 85 degrees Celsius        and/or and wherein the upper core surface of the core layer has        a Shore D hardness of at least 85.

The panel according to the present invention has several benefits overpanels according to the prior art. The combination of a core layercomprising at least one mineral material and at least one polymer a toplayer comprising at least one ply of resin impregnated paper, wherein atleast one ply of paper is impregnated with a resin compositioncomprising at least one thermosetting resin and/or optionally at leastone polymeric adhesive and wherein the core layer has a Vicat softeningtemperature of at least 80 degrees Celsius, preferably at least 85degrees Celsius and/or and wherein the upper core surface of the corelayer has a Shore D hardness of at least 85 results in a panel havingthe waterproof benefits of an PVC panel but also the beneficial scratchresistance of a panel finished with a resin impregnated paper. The useof a core layer having a Vicat softening temperature of at least 80degrees Celsius and an upper core surface of the core layer having aShore D hardness of at least 85, preferably at ambient temperatureand/or at a temperature of 23 degrees Celsius, results in a core layerhaving a relatively high hardness whilst the core composition has theability to maintain this hardness when being heated up, such as duringattachment of the top layer(s). Hence, the combination of thesetechnical characteristics prevents deformation of the core layer duringproduction, use and/or handling. This technical effect was surprisinglyfound as a person skilled in the art would not consider the synergybetween hardness of the core layer and Vicat softening point topositively contribute to lamination of a paper layer at elevatedtemperatures. A person skilled in the art might consider either of thesetwo as a contributing feature, but not a synergy of the above. The panelaccording to the present invention further benefits of a relatively goodshrinking rate wherefore characteristic deformation of the panel, forexample during hot pressing, is prevented. This can at least partiallybe explained by the use of a core layer comprising a composite materialcomprising at least one mineral material and at least one polymer andhaving a Vicat softening temperature of at least 80 degrees Celsiusand/or a Shore D hardness of at least 85. The use of at least onemineral material in the core layer is conceived to impart a sufficientrigidity, advantageously higher than 4000 Mpa MOE and 22 Mpa MOR therebyensuring dimensional stability and toughness of the panel. The use of atleast one polymer in the core layer is conceived to impart flexibilitycharacteristics to the panel when deemed necessary, or for example whenflexibility is required to achieve engagement of a locking mechanism, ifapplied, advantageously lower than 9000 Mpa and 36 Nm MOR. The corelayer according to the present invention can provide rigidity andstrength to allow, for example, a floating installation, but is alsosuitable to provide a substantially flat surface on which a top layercan be efficiently attached. The core layer according to the presentinvention is in particular configured and suitable for use in a thermobonding process. That the at least one top layer comprises at least oneply of resin impregnated paper, wherein at least one ply of paper isimpregnated with a resin composition comprising at least onethermosetting resin and/or at least one polymeric adhesive results inthe top layer being directly attachable to the core layer, for examplevia applying heat and/or pressure, without the need of an intermediateadhesive layer whilst the top layer has a substantially good strengthand scratch resistance.

When it is referred to Vicat softening temperature also softeningtemperature can be meant. The top layer can also be referred to asdecorative top layer. At least one ply of resin impregnated paper top.The top layer is typically a ply of cured resin impregnated paper. Atleast one ply of paper can also be a cellulose and/orlignocellulose-based ply within the scope of the present invention. Itis for example conceivable that lignocellulose is applied as a pulp anddried to form a ply. The at least one polymeric adhesive, if applied,can also be referred to as a polymer adhesive and/or as polymericadhesive compound. When it is referred to a core layer said layer couldalso be called a carrier layer, carrier plate, carrier, core and/orpanel core.

Preferably, at least one ply of resin impregnated paper is in directcontact with the upper core surface of the core layer. Hence, at leastone ply of resin impregnated paper is directly attached to the uppercore surface of the core layer. Preferably at least one ply of paperwhich is impregnated with a resin composition comprising at least onepolymeric adhesive is in direct contact with the upper core surface ofthe core layer. Due to the combination of the ply of paper which isimpregnated with a resin composition comprising at least onethermosetting resin and/or at least one polymeric adhesive and the corelayer according to the present invention the both layers can be attachedwithout the requirement of an adhesive layer in between said layers.Said attachment can for example be done via thermo bonding such as byapplying heat and/or pressure. Hence, the use of an adhesive layer inbetween the top layer and the core layer can be omitted.

In a preferred embodiment, at least one ply of resin impregnated papercomprises at least one polymeric adhesive, preferably at least 1 wt % ofpolymeric adhesive and preferably at least 5 wt % of polymeric adhesive.It is also conceivable that at least one ply of resin impregnated papercomprises in the range of 1 wt % to 20 wt % of polymeric adhesive,preferably in the range of 2.5 wt % to 15 wt % of polymeric adhesive,more preferably in the range of 5 wt % to 10 wt % of polymeric adhesive.If applied, the polymeric adhesive applied in the ply or plies of resinimpregnated paper can be of importance for the bonding between the toplayer and the core layer. It is for example conceivable that at leastone polymeric adhesive is grafted inside the top layer. It is alsoconceivable that the resin composition comprises at least 1 wt % ofpolymeric adhesive and preferably at least 5 wt % of polymeric adhesive.It is also conceivable that the resin composition comprises in the rangeof 1 wt % to 20 wt % of polymeric adhesive, preferably in the range of2.5 wt % to 15 wt % of polymeric adhesive, more preferably in the rangeof 5 wt % to 10 wt % of polymeric adhesive. It is for exampleconceivable that at least one polymeric adhesive of the resincomposition comprises polyurethane, polyester and/or a polyepoxide, suchas but not limited to epoxy resin. At least one polymeric adhesive ofthe resin composition can for example be polyurethane, polyester and/ora polyepoxide.

The thermosetting resin may for example comprise phenolic resin,melamine resin and/or formaldehyde resin. The thermosetting resin mayfor example also comprise melamine formaldehyde.

In a preferred embodiment, the cellulose content of at least one ply ofresin impregnated paper has a weight of at least 40 grams, preferably atleast 70 grams. It is also conceivable that at least one ply of paper ofthe top layer has a weight of at least 25 grams, preferably at least 40grams, more preferably at least 70 grams. The paper, or resinimpregnated paper, can for example have a weight in the range of 70 to80 grams. The resin load of at least one ply of resin impregnated paperis preferably at least 90%, more preferably at least or substantially100%. A substantially fully resin impregnated paper is beneficial forthe waterproofness of the top layer and for the scratch resistancethereof.

With regard to the core layer, it is preferred that at least one polymerof the composite material is a thermoplastic polymer and/or at least onepolymer of the composite material is an elastomer. The use of at leastone thermoplastic or elastomeric polymer in the core layer is conceivedto impart flexibility characteristics to the panel when deemednecessary, for example when flexibility is required to achieveengagement of a locking mechanism. At least one polymer of the compositematerial can for example chosen from the group of polyvinylchloride(PVC), polypropylene (PP), polyethylene terephthalate (PET), polystyrene(PS), polyethylene (PE), polyurethane (PU), acrylonitrile butadienestyrene (ABS) and/or co-polyester (CPE).

It is further preferred that at least one mineral material of thecomposite material is a magnesium-based mineral material, in particularchosen from the group of magnesium oxide (MgO), magnesium chloride (MgClor MOC cement) and/or magnesium oxysulfate (MOS cement). It is alsoconceivable that at least one mineral material of the composite materialcomprises calcium carbonate (CaCO3), chalk, clay, calcium silicateand/or talc. Said materials are known to provide a good rigidity to thecore layer.

In a beneficial embodiment, the composite material of the core layer hasa ratio of mineral material to polymer of at least 3:1. Such relativelylarge percentage of mineral material provides a good rigidity anddimension stability to the core layer whilst the polymer fraction issufficient to provide a desired level of flexibility. This compositionis also beneficial to obtain a desired shrinking rate, in particular ofbelow 0.05%. The content of mineral material may also have a positiveeffect on the desired minimum Shore D hardness of the upper core surfaceof the core layer. The upper core surface of the core layer preferablyhas a Shore D hardness of at least 85. It is also conceivable that theupper core surface of the core layer has a Shore D hardness in the rangeof 85 to 95. The core layer having a ratio of mineral material topolymer of at least 3:1 may also lead to the core layer having arelatively high surface energy which is positive for bonding between thecore layer and the top layer according to the present invention.

The addition of at least one Vicat modifier, in particular to thecomposite material of the core layer, may also further improve thematerial properties of the core layer. The composite material of thecore layer may for example comprise at least one additive configured toincrease the Vicat softening temperature. The Vicat softeningtemperature of the core layer is preferably at least 80 degrees Celsius.It is also conceivable that the Vicat softening temperature is at least82 degrees Celsius, at least 83 degrees Celsius, at least 84 degreesCelsius or at least 85 degrees Celsius. It is also conceivable that theVicat softening temperature of the core layer is in the range of 80 to95 degrees Celsius, or in the range of 85 to 95 degrees Celsius. TheVicat softening temperature of the core layer could for example also besubstantially 90 degrees Celsius. Optionally, the Vicat softeningtemperature of the core layer can be higher than 95 degrees Celsius. Itis also conceivable that the composite material has a Vicat softeningtemperature of at least 80 degrees Celsius, preferably at least 85degrees Celsius. At least one additive could for example compriseacrylonitrile styrene acrylate (ASA), acrylonitrile butadiene styrene(ABS), a thermoset system and/or an epoxy system. At least one additivecan also be a Vicat modifier or referred to as Vicat modifier.

In an alternative embodiment, it is possible that at least one polymerof the composite material is a thermosetting polymer. Hence , it is alsoconceivable that at least one polymer of the composite material of thecore layer comprises at least one phenolic resin, melamine resin and/orformaldehyde resin. The applied resin can for example be a thermosettingresin. It is also beneficial if the composite material of the core layercomprises at least one thermosetting resin and/or at least one polymericadhesive. It is for example conceivable that in case the compositematerial comprises at least one thermosetting resin and/or at least onepolymeric adhesive which equal the at least one thermosetting resinand/or at least one polymeric adhesive applied in the resin compositionof at least one resin impregnated ply of paper of the top layer.

In a beneficial embodiment of the panel, the upper core surface of thecore layer has a surface energy of at least 50 dyn/cm. Thischaracteristic enables good adhering of a resin impregnated ply.Thermoplastics such as PVC, PET, PP and the like typically have a ratherlow surface energy of less than 50 dyn/cm and often even less than 40dyn/cm which make a core layer made of said materials unsuitable foradhering a resin paper directly. The surface energy of the core layerbeing below a required value can cause delamination of the resinimpregnated ply or plies of the top layer, in particular when the panelis exposed to water and/or heat for a period of time. It is for exampleconceivable that the surface energy of the core layer is increased bymeans of a plasma or corona treatment of said surface. An appropriatesynergy of surface energy and roughness can positively contribute theprevention of delamination. It is in particular preferred that the corelayer has a (surface) roughness (Ra) of at least 0.5 μm. Morepreferably, the roughness of the core layer is at least 1 μm. Hence, theupper core surface of the core layer may have a roughness of at least0.5 μm, preferably at least 1 μm. These characteristic enables properbonding between the upper core layer and the top layer, in particularthe resin composition of the top layer.

The core layer can for example have a modulus of elasticity, orrigidity, of at least 3500 MPa, in particular when tested according toEN310 or ASTM D790. The thickness of the core layer is preferablybetween 3 and 9 mm, more preferably between 4 mm and 5.5 mm or between5.5 mm and 7 mm. In a beneficial embodiment, the density of the corelayer is at least 1200 kg/m3, and preferably at least 1400 kg/m3. It isalso conceivable that the density of the core layer is in the range of1600 to 2100 kg/m3.

It is also conceivable that the bottom core surface of the core layerhas a Shore D hardness of at least 85 or in the range of 85 to 95. Thisis in particular beneficial in case a backing layer is applied. Thepanel according to the present invention may comprise at least onebacking layer comprising at least one ply of resin impregnated paper,wherein at least one ply of paper is impregnated with a resincomposition comprising at least one thermosetting resin and/or at leastone polymer adhesive. It is conceivable that the backing layersubstantially equals the top layer. Hence, any of the described toplayer could also be applied as backing layer attached to a bottom coresurface of the core layer. The backing layer, if applied, can bedirectly attached to the bottom core surface of the core layer. Thebacking layer can for example be a balancing layer. The bottom coresurface of the core layer can have equal characteristics as the uppercore surface. In a preferred embodiment is the weight of the backinglayer is higher than the weight of the top layer. It is for exampleconceivable that the backing layer has a weight of at least 70 grams,preferably at least 100 grams, more preferably at least 120 grams. Arelatively heavy backing layer is beneficial for the balancing functionof the backing layer. The total paper weight and/or resin load of thebacking layer can for example be at least the same or higher asrespectively the total paper weight and/or resin load of the top layer.Hence, it is conceivable that the panel comprises at least one backinglayer preferably attached to the bottom surface of the lower core layerwhich substantially differs from the top layer. The backing layer mayprovide a protective function for the core layer and thus for the panelas such. An bottom surface of the backing layer may for example comprisean adhesive layer. It is also conceivable that the backing layer is abalancing layer, preferably configured for stabilization and/orprotection of the panel. A balancing layer may for example preventcupping, warping and/or bowing of the panel. The balancing layer couldalso be referred to as stabilizing layer. The presence of a backinglayer may further contribute to the acoustic performance of the panel asthe backing layer may have sound dampening properties and/or to the easeof installation of the panel. Further, the backing layer may form amoist barrier. The backing layer can also be made of a polymer material,for example but not limited to polyurethane. It is also conceivable thatthe panel comprises a combination of any of the mentioned examples ofpossible backing layers. Further, the backing layer may also be a soundabsorbing layer. Such sound absorbing backing layer may contribute tothe acoustic properties of the panel. Such backing layer may also bereferred to as acoustic layer. The backing layer may be composed of afoamed layer, preferably a low density foamed layer, of ethylene-vinylacetate (EVA), irradiation-crosslinked polyethylene (IXPE), expandedpolypropylene (XPP) and/or expanded polystyrene (XPS). However, it isalso conceivable that the backing layer comprises nonwoven fibers suchas natural fibers like hemp or cork, and/or recycled/recyclable materialsuch as PET. The backing layer, if applied, preferably has a densitybetween 65 kg/m3 and 300 kg/m3, most preferably between 80 kg/m3 and 150kg/m3.

At least one top layer may comprise at least one decor layer. It is forexample conceivable that the top layer is a decorative top layer. It isalso conceivable that at least one ply of paper is a decor paper. Thepanel may optionally comprise at least one wear layer. The wear layercould either form part of the top layer or the wear layer can formintegral part of the top layer. At least one ply of resin impregnatedpaper can be a substantially transparent ply. It is further conceivablethat at least one top layer comprises multiple plies of resinimpregnated paper, wherein at least one ply of paper, and preferablyeach ply of paper, is impregnated with a resin composition comprising atleast one thermosetting resin and/or at least one polymeric adhesive. Incase multiple plies of resin impregnated paper are applied, it isbeneficial if at least the bottom ply, which is attached to the uppercore layer, comprises at least one polymer adhesive. Since the polymeradhesive is an important component for the bonding between the top layerand the core layer, it is of preference that at least the bottom layerof the layer of plies, or ply, which is in contact with the coresurface, is impregnated with a resin composition comprising at least onethermosetting resin and/or at least one polymeric adhesive.

Several compositions of a top layer comprising at least one ply ormultiple plies of resin impregnated paper are conceivable. It is forexample conceivable that at least one ply of paper is a decor paper. Itis also conceivable that at least one ply of paper is a reinforcingpaper. The use of a transparent ply of paper is also conceivable. Incase a plurality of plies is applied, different types of papers can beused. An embodiment is for example imaginable wherein the top layercomprises from top to bottom at least one first ply of transparent paperof at least 50 g which is impregnated with at least one thermosettingresin and comprising a plurality of abrasion resistant particles and/orat least one antibacterial agent and at least one second ply of decorpaper of at least 70 g, impregnated with at least one thermosettingresin and/or at least one polymeric adhesive.

An embodiment is conceivable wherein the top layer comprises a pluralityof abrasion resistant particles. Said abrasion resistant particles arepreferably chosen from the group of aluminum oxide, corundum, siliconcarbide, titanium dioxide, titanium oxide and/or diamond particles. Itis for example conceivable that the abrasion resistant particles aredispersed in the resin composition of the top layer. In case a wearlayer is applied, it is also conceivable that the wear layer comprises aplurality of abrasion resistant particles. The abrasion resistantparticles may then for example be dispersed in the wear layer. In casethe top layer comprises multiple plies of resin impregnated paper,preferably at least one layer comprises a plurality of abrasionresistant particles, more preferably at least the upper ply of the pliescomprises said abrasion resistant particles. Alternatively, it is alsoconceivable that the abrasion resistant particles are applied in theuncured or semi cured resin composition, such that the abrasionresistant particles are applied over the plurality of plies after thecross linking between layers.

The top layer may further comprise at least one resin impregnated ply ofpaper comprising at least one antibacterial agent, preferably zinc oxide(ZnO) and/or silver nanoparticles or the like. It is also conceivablethat the resin composition with which at least one ply of paper isimpregnated comprises at least one antibacterial agent, preferably metaloxides such as titanium dioxide (TiO2), zinc oxide (ZnO), orisothiazolinone, zinc pyrithione, thiabendazole, and/or silvernanoparticles. The presence of at least one antibacterial agent can bebeneficial in case it desired to apply the floor panel or floor coveringmade of such panel for business, industries or areas where a highhygiene standard is present. In case a wear layer or overlay is applied,it is also conceivable that the antibacterial agent is present in thewear layer or overlay. The antibacterial agent may form integral part ofthe top layer. A panel comprising a top layer which comprises at leastone antibacterial agent typically provide a much better protectionagainst bacteria, fungus, parasites and/or viruses compared to panelswhich are covered with an antibacterial agent.

It is beneficial if at least one top layer and at least one core layerare bonded via the provision of heat and/or pressure. At least one toplayer and at least one core layer can for example be bonded via thermobonding. It is beneficial to apply thermo bonding as for the use of anintermediate adhesive layer between the top layer and the core layer canbe omitted. The use of the core layer and top layer according to thepresent invention allow the application of a thermo bonding process.

In a preferred embodiment, the panel comprises two pairs of oppositeside edges, wherein at least one pair of opposite side edges, andpreferably each pair of opposite side edges, is provided withcomplementary coupling parts. The core layer of the panel according tothe present invention may comprise at least one pair of opposing (side)edges, said pair of opposing (side) edges comprising complementarycoupling parts configured for mutual coupling of adjacent panels. Thecoupling parts may form part of the core layer. The coupling parts ofthe panel may for example be interlocking coupling parts, which arepreferably configured for providing both horizontal and verticallocking. Interlocking coupling parts are coupling parts that requireelastic deformation, a click or a movement in multiple directions tocouple or decouple the parts with or from each other. Any suitableinterlocking coupling parts as known in the art could be applied. Anon-limiting example is an embodiment wherein a first edge of said firstpair of opposing edges comprises a first coupling part, and wherein asecond edge of said first pair of opposing edges comprises acomplementary second coupling part, said coupling parts allowing aplurality of panels to be mutually coupled; wherein the first couplingpart comprises a sideward tongue extending in a direction substantiallyparallel to a plane defined by the panel, and wherein the secondcoupling part comprises a groove configured for accommodating at least apart of the sideward tongue of another panel, said groove being definedby an upper lip and a lower lip. It is conceivable the complementarycoupling parts require a downward scissoring motion when engaging, orare locked together by means of a horizontal movement. It is furtherconceivable that the interconnecting coupling parts comprise a tongueand a groove wherein the tongue is provided on one side edge of one pairof opposing side edges, and the groove is provided on the other sideedge, or an adjacent side relative to that of the tongue, of the samepair of opposing side edges. Such a design of a coupling mechanism iswell-known in the art and has proven highly suitable for panels forfloor coverings such as a floating floor. In a further embodiment it ispossible that the interconnecting coupling parts have an interlockingfeature which prevents interconnected panels from any free movement(play). Such an interlocking feature may be a projection and arespective recess provided on the respective opposing side edges bywhich neighboring panels interlock with each other. It is conceivablefor provisions of reinforcement in the interlocking coupling parts toimprove strength and prevent breakage thereof during installation of thepanels. For example, the complementary or interlocking coupling partsmay be reinforced with materials such as but not limited to fiberglassmesh, reinforcing sheets, carbon fibers, carbon nanotubes, ceramics,glass, arrays of metallic or non-metallic rods, or polymer compoundsintegrally formed in the core layer. It is also conceivable that astrengthening coat layer of micro or nanotechnology is added on thesurface of the interlocking coupling parts. The panel according to thepresent invention and/or the panel obtained via the method according tothe present invention is suitable for use in flooring, wall or ceilingcoverings preferably featuring a locking mechanism. As such a ‘floating’covering can be assembled by interconnecting the individual panels witheach other at all four sides, without the need for adhesives.

The invention also related to the alternative embodiment wherein thedecorative panel, in particular a floor panel, wall panel or ceilingpanel, the panel comprising at least one core layer; the core layercomprising an upper core surface and a bottom core surface and two pairsof opposing side edges, wherein the core layer comprises at least onethermoplastic binder and at least one filler, and at least one top layercomprising at least one ply of resin impregnated paper, wherein at leastone ply of paper is impregnated with at least one resin compositioncomprising at least one thermosetting resin and/or at least one polymeradhesive, wherein the core layer has a Vicat softening temperature of atleast 80 degrees Celsius, preferably at least 85 degrees Celsius and/orwherein the upper core surface of the core layer has a Shore D hardnessof at least 85. The core layer may further comprise at least oneadditive, for example as described in the present application. The corelayer can be a mineral composite comprising at least one thermoplasticmaterial.

The panel according to the present invention may even have a shrinkingrate which is lower than 0.15%, and in particular lower than 0.05%, whenmeasured, for example, according to ISPO 23999.

The invention also relates to a method for producing a decorative panel,in particular a floor panel, wall panel or ceiling panel, in particularaccording to any of the embodiment according to the present invention,the method comprising the steps of:

-   -   a) providing at least one core layer, the core layer comprising        an upper core surface and a bottom core surface, which core        layer comprises a composite material comprising at least one        mineral material and/or at least one polymer, wherein the core        layer has a softening temperature of at least 80 degrees        Celsius, preferably at least 85 degrees Celsius and/or wherein        the upper core surface of the core layer has a Shore D hardness        of at least 85;    -   b) providing at least one top layer comprising at least one ply        of resin impregnated paper upon the upper core surface of said        core layer, wherein at least one ply of paper is impregnated        with a resin composition comprising at least one thermosetting        resin and/or at least one polymeric adhesive;    -   c) applying a pressure of at least 12 MPa and a heat of at least        130 degrees Celsius onto the upper surface of the top layer for        a first predetermined amount of time;    -   d) reducing the temperature to a value below 40 degrees Celsius        whilst remaining the pressure of at least 12 MPa for a second        predetermined amount of time.

The method according to the present invention enables the provision of apanel according to the present invention in a relatively simple andcommercially interesting way. The applied core layer has a relativelyhigh hardness whilst the core composition has the ability to maintainthis hardness when being heated up, during attachment of the toplayer(s). The method according to the present invention further does notaddress the problem of thermal expansion under heat of the core layer aswell as the shrinking under heat of the resin impregnated ply of paperof the top layer due to the chosen characteristics. Undesired bendingand/or cupping of the final product can hence be prevented. Thepreferred predetermined time intervals are dependent on several factors.The first predetermined amount of time is preferably in the range of 30to 60 minutes, more preferably in the range of 40 to 50 minutes. Thesecond predetermined amount of time can for example be in the range of 5to 30 minutes, preferably in the range of 10 to 20 minutes. It is alsoconceivable that the first and/or second predetermined amount of timeare in the range of 40 to 45 minutes. It is preferred that the pressureand/or heat is applied via at least one embossing element. The embossingelement can for example be an embossing plate. The use of an embossingelement can provide a predetermined surface structure onto the uppersurface of the top layer, which may be desired for technical and/oraesthetic reasons. The temperature applied during step c) is preferablyin the range of 130 to 150 degrees Celsius. However, it is alsoconceivable that the temperature applied during step c) is above 150degrees Celsius. It is conceivable that the upper core surface of thecore layer is annealed, sanded and/or corona treated prior to step c).Such treatment may further increase for example the surface energy ofthe core layer, which can be of positive influence for the bondingprocess. The method may further comprise the of annealing at atemperature of at least 90 degrees Celsius and a substantially constantpressure of at least 1 Mpa for at least 1 minute, which can be referredto as step e). Alternatively or additionally, the core layer could beannealed, for example at a temperature of at least 90 degrees Celsiusand a substantially constant pressure of at least 1 Mpa for at least 1minute, prior to step c).

The method may further comprise the provision and/or attachment of atleast one backing layer, for example an embodiment thereof as describedfor the present invention. The method may also comprise the step ofmachining of at least two edges of the panel which that complementarycoupling parts are provided.

The invention will now be elucidated into more detail with reference tothe following non-limitative clauses.

1. Decorative panel, in particular a floor panel, wall panel or ceilingpanel, the panel comprising:

-   -   at least one core layer comprising an upper core surface and a        bottom core surface, wherein the core layer comprises a        composite material preferably comprising at least one mineral        material and/or at least one polymer; and    -   at least one top layer comprising at least one ply of resin        impregnated paper;    -   wherein at least one ply of paper is impregnated with a resin        composition comprising at least one thermosetting resin and/or        at least one polymeric adhesive;    -   wherein the core layer has a Vicat softening temperature of at        least 80 degrees Celsius and/or wherein the upper core surface        of the core layer has a Shore D hardness of at least 85.        2. Panel according to clause 1, wherein at least one ply of        resin impregnated paper is in direct contact with the upper core        surface of the core layer.        3. Panel according to any of the previous clauses, wherein at        least one ply of resin impregnated paper comprises at least 1 wt        % of polymeric adhesive, preferably at least 5 wt %.        4. Panel according to any of the previous clauses, wherein at        least one polymeric adhesive of the resin composition comprises        polyurethane, polyester and/or a polyepoxide.        5. Panel according to any of the previous clauses, wherein at        least one ply of resin impregnated paper has a weight of at        least 40 grams, preferably at least 70 grams.        6. Panel according to any of the previous clauses, wherein the        resin load of at least one ply of resin impregnated paper is        substantially 100%.        7. Panel according to any of the previous clauses, wherein at        least one polymer of the composite material is a thermoplastic        polymer and/or at least one polymer of the composite material is        thermosetting polymer.        8. Panel according to any of the previous clauses, wherein at        least one polymer of the composite material is chosen from the        group of polyvinylchloride, polypropylene, polyethylene        terephthalate, polystyrene, polyethylene, polyurethane,        acrylonitrile butadiene styrene and/or co-polyester.        9. Panel according to any of the previous clauses, wherein at        least one mineral material of the composite material is a        magnesium-based mineral material, in particular chosen from the        group of magnesium oxide, magnesium chloride and/or magnesium        oxysulfate.        10. Panel according to any of the previous clauses, wherein at        least one mineral material of the composite material comprises        calcium carbonate, chalk, clay, calcium silicate and/or talc.        11. Panel according to any of the previous clauses, wherein the        composite material has a ratio of mineral material to polymer of        at least 3:1.        12. Panel according to any of the previous clauses, wherein the        composite material further comprises at least one additive        configured to increase the Vicat softening temperature.        13. Panel according to clause 12, wherein additive comprises        acrylonitrile styrene acrylate, acrylonitrile butadiene styrene,        a thermoset system and/or an epoxy system.        14. Panel according to any of the previous clauses, wherein the        upper core surface of the core layer has a surface energy of at        least 50 dyn/cm.        15. Panel according to any of the previous clauses, wherein the        upper core surface of the core layer has a roughness of at least        0.5 μm, preferably at least 1 μm.        16. Panel according to any of the previous clauses, wherein the        thickness of the core layer is between 3 and 9 mm, preferably        between 4 mm and 5.5 mm or between 5.5 mm and 7 mm.        17. Panel according to any of the previous clauses, wherein the        core layer has a density of at least 1400 kg/m3.        18. Panel according to any of the previous clauses, wherein the        bottom core surface of the core layer has a Shore D hardness of        at least 85.        19. Panel according to any of the previous clauses, comprising        at least one backing layer comprising at least one ply of resin        impregnated paper, wherein at least one ply of paper is        impregnated with a resin composition comprising at least one        thermosetting resin and/or at least one polymer adhesive.        20. Panel according to clause 19, wherein the weight of the        backing layer is higher than the weight of the top layer.        21. Panel according to any of the previous clauses, wherein the        top layer comprises at least one decor layer and/or wherein the        top layer comprises at least one wear layer.        22. Panel according to any of the previous clauses, wherein at        least one top layer comprises multiple plies of resin        impregnated paper, wherein at least one ply of paper is        impregnated with a resin composition comprising at least one        thermosetting resin and/or at least one polymeric adhesive        23. Panel according to any of the previous clauses, wherein the        top layer comprises a plurality of abrasion resistant particles,        in particular chosen from the group of aluminum oxide, corundum,        silicon carbide, titanium dioxide, titanium oxide and/or diamond        particles.        24. Panel according to any of the previous clauses, wherein the        top layer comprises at least one resin impregnated ply of paper        comprising at least one antibacterial agent, preferably zinc        oxide and/or silver nanoparticles.        25. Panel according to any of the previous clauses, wherein the        top layer and the core layer are bonded via thermo bonding.        26. Panel according to any of the previous clauses, wherein the        panel comprises two pairs of opposite side edges, wherein at        least one pair of opposite side edges, and preferably each pair        of opposite side edges, is provided with complementary coupling        parts.        27. Method for producing a decorative panel, in particular a        floor panel, wall panel or ceiling panel, in particular        according to any of the previous clauses, comprising the steps        of:    -   a) providing at least one core layer, the core layer comprising        an upper core surface and a bottom core surface, which core        layer comprises a composite material comprising at least one        mineral material and at least one polymer, wherein the core        layer has a softening temperature of at least 80 degrees        Celsius, preferably at least 85 degrees Celsius and/or wherein        the upper core surface of the core layer has a Shore D hardness        of at least 85;    -   b) providing at least one top layer comprising at least one ply        of resin impregnated paper upon the upper core surface of said        core layer, wherein at least one ply of paper is impregnated        with a resin composition comprising at least one thermosetting        resin and/or at least one polymeric adhesive;    -   c) applying a pressure of at least 12 MPa and a heat of at least        130 degrees Celsius onto the upper surface of the top layer for        a first predetermined amount of time;    -   d) reducing the temperature to a value below 40 degrees Celsius        whilst remaining the pressure of at least 12 MPa for a second        predetermined amount of time.        28. Method according to clause 27, wherein the first        predetermined amount of time is in the range of 30 to 60        minutes, preferably in the range of 40 to 50 minutes and/or        wherein the second predetermined amount of time is in the range        of 5 to 30 minutes, preferably in the range of 10 to 20 minutes.        29. Method according to clause 27 or 28, wherein the pressure        and/or heat is applied via at least one embossing element.        30. Method according to any of clauses 27-29, wherein the        temperature applied during step c) is in the range of 130 to 150        degrees Celsius.        31. Method according to any of clauses 27-30, wherein the upper        core surface of the core layer is be annealed, sanded and/or        corona treated prior to step c).        32. Method according to any of clauses 27-31, comprising step d)        annealing at a temperature of at least 90 degrees Celsius and        substantially constant pressure of at least 1 Mpa for at least 1        minute.

It will be apparent that the invention is not limited to the examplesdescribed, but that numerous variants are possible within the scope ofthe attached claims that will be obvious to a person skilled in the art.It is not necessary to elaborate on examples of all conceivablecombinations of the above-described inventive concepts, as a personskilled in the art will understand numerous inventive concepts can be(re)combined in order to arrive at a specific application.

The verb “comprise” and conjugations thereof used in this patentpublication are understood to mean not only “comprise”, but are alsounderstood to mean the phrases “contain”, “substantially consist of”,“formed by” and conjugations thereof.

1. A decorative panel, the panel comprising: at least one core layercomprising an upper core surface and a bottom core surface, wherein thecore layer comprises a composite material comprising at least onemineral material and at least one polymer; and at least one top layercomprising at least one ply of resin impregnated paper; wherein at leastone ply of paper is impregnated with a resin composition comprising atleast one thermosetting resin; wherein the core layer has a Vicatsoftening temperature of at least 80 degrees Celsius and wherein theupper core surface of the core layer has a Shore D hardness of at least85.
 2. The panel according to claim 1, wherein the at least one ply ofresin impregnated paper is in direct contact with the upper core surfaceof the core layer.
 3. The panel according to claim 1, wherein the leastone ply of resin impregnated paper comprises at least 1 wt % of at leastone polymeric adhesive.
 4. The panel according to claim 3, wherein theat least one polymeric adhesive of the resin composition comprisespolyurethane, polyester and/or a polyepoxide.
 5. The panel according toclaim 1, wherein the at least one ply of resin impregnated paper has aweight of at least 40 grams.
 6. The panel according to claim 1, whereinthe resin load of the at least one ply of resin impregnated paper is atleast 100%.
 7. (canceled)
 8. The panel according to claim 1, wherein atleast one polymer of the composite material is selected frompolyvinylchloride, polypropylene, polyethylene terephthalate,polystyrene, polyethylene, polyurethane, acrylonitrile butadiene styreneand/or co-polyester.
 9. The panel according to claim 1, wherein at leastone mineral material of the composite material is a magnesium-basedmineral material selected magnesium oxide, magnesium chloride and/ormagnesium oxysulfate.
 10. (canceled)
 11. The panel according to claim 1,wherein the composite material has a ratio of mineral material topolymer of at least 3:1.
 12. The panel according to claim 1, wherein thecomposite material further comprises at least one additive configured toincrease the Vicat softening temperature, wherein the at least oneadditive comprises acrylonitrile styrene acrylate, acrylonitrilebutadiene styrene, a thermoset system and/or an epoxy system. 13.(canceled)
 14. The panel according to claim 1, wherein the upper coresurface of the core layer has a surface energy of at least 50 dyn/cm.15. The panel according to claim 1, wherein the upper core surface ofthe core layer has a roughness of at least 0.5 μm.
 16. (canceled) 17.(canceled)
 18. (canceled)
 19. The panel according to claim 1, comprisingat least one backing layer comprising the at least one ply of resinimpregnated paper, wherein the at least one ply of resin impregnatedpaper is impregnated with a resin composition comprising at least onethermosetting resin.
 20. (canceled)
 21. (canceled)
 22. (canceled) 23.The panel according to claim 1, wherein the top layer comprises aplurality of abrasion resistant particles selected from aluminum oxide,corundum, silicon carbide, titanium dioxide, titanium oxide and/ordiamond particles.
 24. (canceled)
 25. (canceled)
 26. The panel accordingto claim 1, wherein the panel comprises two pairs of opposite sideedges, wherein at least one pair of the opposite side edges, andpreferably each pair of the opposite side edges, is provided withcomplementary coupling parts.
 27. A method for producing a decorativepanel, comprising the steps of: a) providing at least one core layer,the core layer comprising an upper core surface and a bottom coresurface, which core layer comprises a composite material comprising atleast one mineral material and at least one polymer, wherein the corelayer has a softening temperature of at least 80 degrees Celsius andwherein the upper core surface of the core layer has a Shore D hardnessof at least 85; b) providing at least one top layer comprising at leastone ply of resin impregnated paper upon the upper core surface of saidcore layer, wherein at least one ply of paper is impregnated with aresin composition comprising at least one thermosetting resin; c)applying a pressure of at least 12 MPa and a heat of at least 130degrees Celsius onto the upper surface of the top layer for a firstpredetermined amount of time; d) reducing the temperature to a valuebelow 40 degrees Celsius whilst remaining the pressure of at least 12MPa for a second predetermined amount of time.
 28. The method accordingto claim 27, wherein the first predetermined amount of time is in therange of 30 to 60 minutes and/or wherein the second predetermined amountof time is in the range of 5 to 30 minutes.
 29. (canceled)
 30. Themethod according to claims 27, wherein the temperature applied duringstep c) is in the range of 130 to 150 degrees Celsius.
 31. The methodaccording to claim 27, wherein the upper core surface of the core layeris annealed, sanded and/or corona treated prior to step c).
 32. Themethod according to claim 27, comprising step d) annealing at atemperature of at least 90 degrees Celsius and a substantially constantpressure of at least 1 Mpa for at least 1 minute.